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This course is designed
to prepare healthcare professionals to prevent transmission of Hepatitis
C (HCV) and conduct effective client counseling.
After completing the course, the
learner will be able to:
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1. |
Identify the modes of
transmission of HCV |
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2. |
Discuss prevention of HCV |
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3. |
Describe the risk factors
for acquiring HCV infection
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4. |
Identify the treatment for
HCV |
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5. |
Discuss post testing
counseling |
Hepatitis C (HCV) is the most
common, chronic bloodborne pathogen
in the United States (US) (Pearlman,
2004). According to the Centers for
Disease Control (CDC) US statistics,
approximately 3.2 million people
have chronic HCV infection causing
an estimated 8,000-10,000 deaths
every year (CDC, 2008).
HCV is most prevalent among people
born during 1945-1965. The majority
of these people were probably
infected during the 1970s and 1980s
when HCV infection rates were
highest (CDC, 2008). There is a
decreasing incidence of HCV in the
US. However, because of the
significant lag time between
infection onset and hepatic
symptoms, the prevalence of HCV
related chronic liver disease is
increasing (Pearlman, 2004). The
following are the Center for Disease
Control (CDC) statistics about HCV
incidence (CDC, 2008, pg. 1).
HCV is transmitted primarily through
large or repeated direct
percutaneous exposures to blood.
Some people are at higher risk of an
HCV infection than the general
population.
People at increased risk for HCV
infection (CDC, 2008, pg. 1):
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1. |
Current or former injection
drug users |
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2. |
Recipients of clotting
factor concentrates made
before 1987 |
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3. |
Recipients of blood
transfusions or solid organ
transplants before July 1992 |
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4. |
Chronic hemodialysis clients
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5. |
Persons with known exposures
to HCV, such as healthcare
workers after needlesticks
involving HCV-positive blood
recipients of blood or
organs from a donor who
tested HCV-positive |
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6. |
Persons with HIV infection
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7. |
Children born to
HCV-positive mothers |
The most common transmission means
use to be blood transfusion, but
that is now rare in the US since
blood screening became available in
1992. The occurrence rate of
transmission from transfusion is now
one chance per two million
transfusions (CDC, 2008).
Now the most common means of
transmission is injection drug use.
One third of injection drug users
age 18-30 are HCV infected, but the
occurrence in older or previous
injection drug users is about
70%-90% (CDC, 2008). The higher
prevalence is due to needle sharing
during the 1970s and 1980s.
Educational initiatives have reduced
this transmission mode.
HCV prevalence among healthcare
workers is not higher than in the
general population. It averages
1%-2%, and is 10 times lower than
that for HBV infection. A history of
unintentional needle-stick injury
was the only occupational risk
factor independently associated with
HCV infection. The risk for HCV
infection after a needlestick or
sharps exposure to HCV-positive
blood is approximately 1.8% (range:
0%-10%). When healthcare
professionals understand and adhere
to standard precautions, safe
injection practice, and other
guidance for reducing bloodborne
pathogen exposure risk, transmission
in healthcare settings is infrequent
(CDC, 2008).
The subject of HCV transmission from
a healthcare worker to a client is
controversial. Transmission has been
reported rarely, but more than half
the reported cases had other risk
factors (Pearlman, 2004). "CDC's
recommendations for prevention and
control of HCV infection specify
that persons should not be excluded
from work, school, play, child care,
or other settings on the basis of
their HCV infection status. There is
no evidence of HCV transmission from
food handlers, teachers, or other
service providers in the absence of
blood-to-blood contact" (CDC, 2008,
pg.1).
The average rate of HCV infection
among infants born to HCV-positive,
HIV negative women is 5%-6%. The
average infection rate for infants
born to women co-infected with HCV
and HIV is higher, at 14% to 17%.
Data regarding the relationship
between delivery mode and HCV
transmission are limited. What is
available indicates no difference in
infection rates between infants
delivered vaginally compared with
cesarean-delivered infants. The
transmission of HCV infection
through breast milk has not been
documented. In the studies that have
evaluated breastfeeding in infants
born to HCV-infected women, the
average rate of infection was 4% in
both breastfed and bottle-fed
infants. Breast-feeding is not
contraindicated for HCV-positive
mothers unless the nipples are
cracked and bleeding.
Transmission can occur during sexual
contact with an HCV infected person;
but sexual contact is an inefficient
means of transmission. The same is
true of transmission due to sharing
personal items that are contaminated
with infectious blood, like
toothbrushes and razors (CDC, 2008).
The spread of HCV within a household
is most likely due to direct
percutaneous exposure to the blood
of the infected person.
There is no US data indicating that
people with exposures to tattooing
and body piercing alone are at
increased risk of HCV infection
(CDC, 1998). In other countries, HCV
infection has been associated with
folk medicine practices, tattooing,
body piercing, and commercial
barbering.
Healthcare, emergency medical, and
public safety workers should be
educated regarding the risk for and
prevention of bloodborne infections.
Standard precautions and safe
injection practice should be
implemented to prevent exposure to
blood. Protocols should be in place
for the reporting and follow-up of
percutaneous or permucosal exposures
to blood or body fluids.
Healthcare professionals responsible
for overseeing clients receiving
home infusion-therapy should ensure
that clients and caregivers are
informed of potential risk for
infection with bloodborne pathogens,
and should assess their ability to
use adequate infection-control
practices. Clients and families
should receive training with a
standardized curriculum that
includes appropriate
infection-control procedures, and
these procedures should be evaluated
regularly through home visits.
Intensive efforts must be made to
educate new staff and re-educate
existing staff regarding
hemodialysis-specific infection
control practices. Hemodialysis
center precautions are more
stringent than standard precautions.
Isolation of HCV-positive clients
during dialysis is neither necessary
nor recommended. Routine precautions
for the care of all hemodialysis
clients (CDC, 1998):
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Clients should have specific
dialysis stations assigned
to them, and chairs and beds
should be cleaned after each
use. |
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Gloves should be used
whenever clients or
hemodialysis equipment is
touched. |
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Sharing among clients of
ancillary supplies such as
trays, blood pressure cuffs,
clamps, scissors, and other
nondisposable items should
be avoided. |
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Nondisposable items should
be cleaned or disinfected
appropriately between uses.
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Medications and supplies
should not be shared among
clients, and medication
carts should not be used.
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Medications should be
prepared and distributed
from a centralized area. |
The goals of HCV prevention and
control efforts are: 1) to reduce
the incidence of new infections by
reducing HCV transmission; and 2) to
reduce the risk of chronic liver
disease in HCV-infected individuals
through appropriate medical
management and counseling (CDC,
2001). These goals can be achieved
by identifying persons at risk for
infection and providing them with
education and risk reduction
counseling. The CDC recommends the
following comprehensive strategy to
prevent and control HCV infection
and related disease (CDC, 1998).
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Primary prevention |
Screening and testing of blood, plasma, organ,
tissue, and semen donors |
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Virus inactivation of plasma-derived products |
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Risk-reduction counseling and services |
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Implementation and maintenance of
infection-control practices |
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Secondary prevention |
Identification, counseling, and testing of
people at risk |
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Medical management of infected people |
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Professional and public education
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Surveillance and research |
Monitor disease trends and the effectiveness of
prevention activities and to develop improved
prevention methods |
As part of a complete medical
history for all clients, it is
important to obtain a history of
high-risk exposures associated with
HCV and other bloodborne pathogens,
HCV testing, and appropriate medical
services including substance abuse
treatment. Preventing or changing
behaviors and activities that place
persons at risk for HCV infection
should reduce disease transmission.
Appropriate testing, medical
management and substance abuse
counseling and treatment should
reduce the risk of chronic liver
disease (CDC, 2001).
HCV infection can be detected by
anti-HCV screening tests (enzyme
immunoassay) 4-10 weeks after
infection. Anti-HCV can be detected
in >97% of persons by 6 months after
exposure (CDC, 2008). The following
are the laboratory criteria for
diagnosis of HCV infection developed
by the CDC (2008, pg. 1). Only one
criterion need be met to meet the
diagnosis:
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1. |
Anti-HCV positive (repeat
reactive) by EIA, verified
by an additional more
specific assay (e.g. RIBA
for anti-HCV or nucleic acid
testing for HCV RNA), |
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2. |
HCV RIBA positive, |
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3. |
Nucleic acid test for HCV
RNA positive, |
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4. |
Report of HCV genotype
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5. |
Anti-HCV
screening-test-positive with
a signal to cut-off ratio
predictive of a true
positive as determined for
the particular assay (e.g.,
≥3.8 for the enzyme
immunoassays) as determined
and posted by CDC |
False positive anti-HCV test is
possible. It is important to confirm
a positive anti-HCV test with a
supplemental test, such as RIBA
(recombinant immunoblot assay).
False negative tests can also occur.
People with early HCV infection
might not yet have developed
antibody levels high enough that the
test can measure. In addition, some
persons might lack the immune
response necessary for the test to
work well. In these persons, further
testing such as PCR for HCV RNA may
be considered (CDC, 2008). HCV
testing is recommended for anyone at
increased risk for HCV infection,
all persons with HIV infection, and
clients with signs or symptoms of
liver disease (e.g., abnormal liver
enzyme tests) (CDC, 2008).
Infants born to HCV positive mothers
should not be tested for anti-HCV
until 18 months because the anti-HCV
from the mother might last until
this age. Testing for HCV RNA could
be performed at or after the
infant's first well-child visit at
age 1-2 months if earlier diagnosis
is desired. HCV RNA testing should
then be repeated at a subsequent
visit, independent of the initial
HCV RNA test result (CDC, 2008).
Pregnant women have no greater risk
of being infected with HCV than
non-pregnant women and interventions
to prevent mother-to-child
transmission are lacking. Therefore,
routine anti-HCV testing of pregnant
women is not recommended. Pregnant
women should be tested for anti-HCV
only if they have risk factors for
HCV infection (CDC, 2008).
Institutions should establish
policies and procedures for HCV
testing of people after percutaneous
or permucosal exposures to blood and
ensure that all personnel are
familiar with these policies and
procedures.
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Postexposure follow-up of healthcare, emergency
medical and public safety workers for HCV virus
(CDC, 2008): |
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For the source |
perform baseline testing for anti-HCV |
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For the person exposed to an HCV-positive
source |
perform baseline and follow-up testing,
including baseline testing for anti-HCV and ALT
activity
AND
follow-up testing for anti-HCV (e.g., at 4-6
months) and ALT activity. If earlier diagnosis
of HCV infection is desired, testing for HCV RNA
may be performed at 4-6 weeks |
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Supplemental anti-HCV testing to confirm all
anti-HCV results reported as positive by enzyme
immunoassay |
IG is not effective for postexposure
prophylaxis of HCV. Antiviral agents
(e.g., interferon) are not
recommended to prevent HCV
infection. The mechanisms of the
effect of interferon in treating HCV
are not understood, and an
established infection might need to
be present for interferon to be
effective.
Limited data indicate that antiviral
therapy might be beneficial when
started early in the course of HCV
infection, but no guidelines exist
for administration of therapy during
the acute phase of infection. When
HCV infection is identified early,
the individual should be referred
for medical management to a
specialist in this area.
People who are newly infected with
HCV are usually asymptomatic, so
acute HCV is rarely identified or
reported (CDC, 2008). 20%-30% of
newly infected people have symptoms
that can include (CDC, 2008, pg. 1):
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Fever |
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Fatigue |
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Dark urine |
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Clay-colored stool |
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Abdominal pain |
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Loss of appetite |
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Nausea |
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Vomiting |
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Joint pain |
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Jaundice |
In symptomatic people, the average
time period from exposure to symptom
onset is 4-12 weeks (range: 2-24
weeks) (CDC, 2008).
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HCV Disease Progression
(CDC, 2008) |
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15%-25% |
HCV
cleared from body without treatment and do not
develop chronic infection |
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75%-85% |
Develop chronic infection |
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60%-70% |
Develop chronic liver disease |
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5%-20% |
Develop cirrhosis over a period of 20-30 years |
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1%-5% |
Die
from consequences of chronic infection (i.e.
liver cancer or cirrhosis) |
No clinical or epidemiologic
features among people with acute
infection have been found to be
predictive of either persistent
infection or chronic liver disease.
Most people with chronic HCV
infection are asymptomatic. Most are
not diagnosed until they are
screened for a blood donation or
when elevated alanine
aminotransferase (ALT, a liver
enzyme) levels are detected during
routine examinations (CDC, 2008).
Those people who are symptomatic
have chronic liver disease which can
be mild to severe. The liver disease
can include cirrhosis and liver
cancer. HCV related chronic liver
disease is usually insidious and
progressed slowly without any
symptoms for several decades (CDC,
2008). The leading indication for
liver transplants in the US is
Chronic HCV infection (CDC, 2008).
Data indicate that increased alcohol
intake, being older than 40 at the
time of infection, and being male
are associated with more severe
liver disease. In people with
alcoholic liver disease and HCV
infection, liver disease progresses
more rapidly. Intake of moderate
amounts (>10 grams/day) of alcohol
in clients with chronic HCV may
enhance the disease progression.
More severe liver injury observed in
people with alcoholic liver disease
and HCV infection possibly is
attributable to alcohol-induced
enhancement of viral replication or
increased susceptibility of cells to
viral injury.
Extra hepatic manifestations of
chronic HCV infection occur in 38%
of chronically infected HCV clients
(Pearlman, 2004). Cognitive problems
may be present even in the absence
of clinically significant liver
disease or interferon based therapy
(Pearlman, 2004). Diabetes mellitus
occurs three times more frequently
in HCV-infected persons. Other HCV
related manifestations include (CDC,
2008):
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Vitiligo |
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Cryoglobulinemia |
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Membranoproliferative
glomerulonephritis |
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Non-Hodgkin's lymphoma |
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Porphyria cutanea tarda.
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Extra hepatic conditions that have
been reported but definitive
associations of these conditions
with HCV infection have not been
established include (Pearlman,
2004):
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Seronegative arthritis |
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Sjögren syndrome |
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Autoimmune thyroiditis |
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Lichen planus |
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Mooren corneal ulcers |
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Idiopathic pulmonary
fibrosis (Hamman-Rich
syndrome) |
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Polyarteritis nodosa |
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Aplastic anemia |
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B-cell lymphomas |
HCV positive clients should be
evaluated for chronic liver disease
and determination of the need for
hepatitis A and hepatitis B
vaccination. Assessment of liver
functions tests, evaluation of
severity of liver disease and
possible treatment should be done.
Chronic HCV treatment of choice is a
combination therapy of pegylated
interferon and ribavirin. The
addition of polymerase and protease
inhibitors has increased success
rates. The treatment objective is a
sustained virologic response of
undetectable HCV RNA in the client's
blood. The combination therapy of
interferon and ribavirin is
FDA-approved for use in children
ages 3-17 years (CDC, 2008).
Genotyping needs to be done with HCV
positive clients. There are six
distinct HCV genotypes and more than
50 subtypes have been identified.
Genotype 1 is the most common HCV
genotype in the US (CDC, 2008).
Knowing the genotype can help
predict the likelihood of treatment
response and, in many cases,
determine the duration of treatment
(CDC, 2008, pg. 1).
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Clients with genotypes 2 and 3 are almost three
times more likely than clients with genotype 1
to respond to therapy with alpha interferon or
the combination of alpha interferon and
ribavirin. When using combination therapy, the
recommended duration of treatment depends on the
genotype. For clients with genotypes 2 and 3, a
24-week course of combination treatment is
adequate, whereas for clients with genotype 1, a
48-week course is recommended. |
Contraindications to treatment with
interferon include major depressive
illness, cytopenias,
hyperthyroidism, renal
transplantation, and evidence of
autoimmune disease. Interferon
usually causes flu-like symptoms
early in treatment that diminish
with continued treatment. Later side
effects include fatigue, bone marrow
suppression, and neuropsychiatric
effects (e.g., apathy, cognitive
changes, irritability, and
depression). Up to 20% of clients do
not complete the antiviral therapy
because they experience significant
side effects. In addition, some
clients may have conditions, such as
severe cirrhosis which prohibit
treatment.
Ribavirin can induce hemolytic
anemia and can cause problems for
clients with pre-existing anemia,
bone marrow suppression, or renal
failure. These clients should avoid
combination therapy. Hemolytic
anemia caused by ribavirin can be
life threatening for clients with
ischemic heart disease or cerebral
vascular disease. Ribavirin is
teratogenic, and female clients
should avoid becoming pregnant
during therapy (CDC, 1998).
HCV negative people with ongoing
risk factors require counseling
concerning ways to reduce their risk
for infection, referral to substance
abuse treatment if appropriate, and
immunization with hepatitis A and
hepatitis B vaccines (CDC, 2005).
There is no vaccine for HCV, but
research is being done to develop a
vaccine (CDC, 2008).
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Counseling recommended for people who have HCV
infection
(CDC, 2008): |
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There is a low but present risk for transmission
with sex partners. |
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Sharing personal items that might have blood on
them, such as toothbrushes or razors, can pose a
risk to others. |
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Cuts and sores on the skin should be covered to
keep from spreading infectious blood or
secretions. |
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Donating blood, organs, tissue, or semen can
spread HCV to others. |
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HCV
is not spread by sneezing, hugging, holding
hands, coughing, sharing eating utensils or
drinking glasses, or through food or water. |
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Avoid alcohol because it can accelerate
cirrhosis and end-stage liver disease. |
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Check with a health professional before taking
any new prescription pills, over-the counter
drugs (such as non-aspirin pain relievers), or
supplements, as these can potentially damage the
liver. |
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A
support group may be beneficial. |
Syringe and needle-exchange programs
can be effective in reducing the
incidence of bloodborne virus
transmission and do not encourage
the use of illegal drugs. Therefore,
to reduce the risk for HCV infection
among injecting-drug users, local
communities can consider
implementing syringe and
needle-exchange programs.
Strategies to reduce transmission of
HCV have been successful and need to
be maintained. Standard precautions,
safe injection practice, and
infection control practices need to
be followed. Healthcare
professionals need to continue to
educate the public on methods to
reduce transmission, ways to deal
with an HCV infection, and ways to
reduce liver damage if infected.
CDC. (2008). FAQs for Health
Professionals. Retrieved 11/15/08
from
http://www.cdc.gov/hepatitis/HCV/HCVfaq.htm#section1
CDC. (2008). Hepatitis C Virus
Infection, Past or Present.
Retrieved 11/15/08 from
http://www.cdc.gov/ncphi/disss/nndss/casedef/hepatitisccurrent.htm
CDC. (2008). Statistics and
Surveillance. Retrieved 11/15/08
from
http://www.cdc.gov/hepatitis/Statistics.htm#section1.
CDC. (2005). Hepatitis C fact sheet.
Retrieved January 15, 2005, from
www.CDC.gov.
CDC. (2001). National Hepatitis C
prevention strategy: A comprehensive
strategy for the prevention and
control of Hepatitis C virus
infection and its consequences.
Retrieved January 15, 2005, from
www.CDC.gov.
CDC. (1998). Hepatitis C: What
Clinicians and Other Health
Professionals Need to Know, Centers
for MMWR, 47 (No. RR-19).
Pearlman, B. (2004). Hepatitis C
infection: A clinical review.
Southern Medical Journal. 97(4),
365-376. |